Looking at the tread pattern of the Bridgestone Potenza RE003, the wet performance may not be too good. The main groove along the circumference of the tyre is rather narrow and not as wide as say the Michelin PS3. From the way you are describing above, the car is sliding on its own to the right although you are maintaining the steering wheel. Meaning that the tyres are losing traction, causing the car to swerve to the right on its own due to the wet surface.

There may be several scenarios why this is happening, though I can think of two possible causes rather (rather than not-so-possible causes such as ESC not working, something wrong with the car etc.). Take this with a grain of salt as I am not a tyre expert but still, my opinion based on the tyre pattern that I observe :-

1. The tyres. There are very little "cross-horizontal" treads running horizontally across the tyre, on the middle of the tyres as well as the outer sides of the tyres near the sidewall, and the treads are spaced quite far apart especially at the outer side of the tyre near the sidewall/rims. The main groove along the circumference of the tyre is also moderately-sized and not too wide, more to a comfort/silent tyre groove size rather than a performing "all-condition" tyres.

Due to the lack of treads and moderately-sized main groove, there is a lot of rubber contact on the road and the potential of tyre sliding is higher when the road is wet. IN summary, not so good performance in heavy rain. However, on dry roads, the performance is likely to be superb as there is a lot of rubber/road contact.

2. Oil on the road which causes the road to be slippery.

Bridgestone Potenza RE003


Michelin PS3
(Although this image is smaller than the image above, look at the treads and grooves. The main grooves along the circumference of the PS3 are larger than the RE003, and the treads near the sidewall are nearer when compared to the RE003 where the treads are spaced further apart)


This post has been edited by SportyHandling: Nov 17 2015, 09:58 AM

Coincidentally, I was informed by the tyre shop owner that Michelin will be phasing out the Primacy 3ST as there will be new model replacing this tyre very soon. Not too sure how true is this.